Which of the following substances gives a red | vedclass

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(A) The $Lassaigne's$ test is used to detect nitrogen,sulfur,and halogens in organic compounds.When an organic compound contains both nitrogen $(N)$ a

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Thiourea

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(A) The $Lassaigne's$ test is used to detect nitrogen,sulfur,and halogens in organic compounds.When an organic compound contains both nitrogen $(N)$ and sulfur $(S)$,the fusion with sodium metal produces sodium thiocyanate $(NaSCN)$.$Na + C + N + S \rightarrow NaSCN$When this $Lassaigne's$ extract is treated with ferric chloride $(FeCl_3)$,the ferric ions react with thiocyanate ions to form ferric thiocyanate,which has a blood-red color.$Fe^{3+} + 3SCN^- \rightarrow Fe(SCN)_3$ (Blood red color)Among the given options,$Thiourea$ $(NH_2CSNH_2)$ contains both nitrogen and sulfur,thus it will give a positive test for both $N$ and $S$ leading to the formation of $NaSCN$.

List-$I$ (Functional group detection)	List-$II$ (Change observed during detection)
$A$. Unsaturation (Baeyer's test)	$I$. Red colour appears
$B$. Alcoholic group (Ceric ammonium nitrate test)	$II$. Silver mirror appears
$C$. Aldehyde group (Tollen's reagent)	$III$. Violet colour appears
$D$. Phenolic group ($FeCl_3$ test)	$IV$. Discharge of pink colour

Which of the following substances gives a red color when its $Lassaigne's$ extract is treated with alkali and ferric chloride?

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